The invention relates generally to concrete form apparatus and, more specifically, to an assembly of leg members of a shore post component of concrete form systems that does not require welding of the leg members in forming the assembly.
Concrete forming apparatus is in wide use in the construction of buildings, bridges, and other concrete structures. A common system for forming concrete structures uses a plurality of modular form components that are adapted to be assembled into a wide variety of configurations to conform to virtually any architectural requirement. Such forming apparatus components are typically made of metal so that they are strong enough to support the heavy weight of poured concrete and durable so that the components can be reused many times.
A common application of concrete forming apparatus is in the formation of elevated sections, such as floors or horizontal beams of a concrete building. Typically, pluralities of modular form panels are assembled to form the surface on which the concrete will be poured. These panels are supported on metal shore posts that typically are constructed of an inner tube that is received for telescopic movement inside an outer tube. Metal tubes achieve high load capacity and the telescoping tubes provide adjustment to various heights. For corrosion resistance, the tubes may be galvanized.
For convenience and safety, it is desirable to secure the two telescopic tubes to each other so that they do not accidentally fall apart during handling between pours. A known method of securing the two tubes together is to provide the outer tube with a collar of reduced inner diameter. One end of the inner tube is deformed so that it will still slide inside the outer tube but cannot pass through the collar. The non-deformed end of the inner tube is inserted into the end of the outer tube opposite from the collar. An end plate is then attached to the end of the outer tube opposite the collar, thereby trapping the inner tube for telescopic movement inside the outer tube. The end plate is attached either by welding or the use of mechanical fasteners. Welding of galvanized parts, however, presents health concerns for the welders and also results in the formation of areas of the shore post that are not protected by galvanizing. Fasteners require additional materials, assembly time and labor.
The preferred embodiments of the present invention eliminate the need either for welding or the use of mechanical fasteners. The inner tube is deformed after both galvanizing of the parts and assembly of the inner tube inside the outer tube to which an end plate has already been attached.